sounds like potentially too much water in the system or you have an unhappy electrical component once it's heat soaked. Part of me also thinks it could be exhaust gas related, maybe a small crack somewhere that gets stressed under load. Not sure. Doesn't sound like a fun problem.
Need help dialing in my xs900
- Thread starter danielpak_ek9
- Start date
I think that unrestricted 3/8 line is too much water. How hot does the WB get? Can you hold your hand on it for 5 seconds? My guess it's warm at best. Just clamp the line off and go for a quick ride, you'll know real quick if it gains you some power or fixes your other issue.
- Location
- Missouri
You can definitely hold your hand on the waterbox with barely any heat on it. I actually just put a needle seat restrictor on the line I'm gonna take the ski out this week and see what happens. Gonna take some heat measurements of the engine and exhaust and box and go from there . Really appreciate all of y'all's inputs. We may have just found out what the problem might be
- Location
- Missouri
Yeah I actually done some research and a lot of guys are saying the RRP box isnt great at all. It lets water back into the exhaust and to the motor. Paired with my line shooting alot of water into water box as well I'm thinking water maybe going into the engine in some cases..
DylanS
Gorilla Smasher
- Location
- Lebanon Pa
possible. Like I said from what I’m hearing in the videos it sounds like the engine is eating and clearing water when it’s bogging on you but it could be a combination of a few things. The first video the ski sounded very sluggish for the shown setup almost like the prop is too tall. The second video on the first rotation sounded pretty decent so I’m not sure what changes were made in between or if that second video was on a cold motor though. Maybe just camera audio too.
- Location
- Missouri
Nope nothing changed. Once motor runs great it rips. My bet is something to do with too much water
- Location
- Charlotte, NC
It definitely sounds like the pump is too tight for your setup. Obviously there could be other issues as well but a ski with a pump that is too tight can cause several strange issues.
- Location
- Missouri
7/15
Maybe a little tall. And a degree or two can make a world of difference. Just my 2 cents for reference when I ran a 155 OE pump behind my 898, charging Zeel, PFP, 180 domes, I ran a 6/12 and that was about all it wanted. When I went to a Maxx mag 155 I was able to run a 7/12 thin blade/long blade setback behind the same 898 motor setup. OE pumps aren’t as efficient as Mags is my guess. And confirming what you are actually running is going to be tough as the Watcon gages don’t go that flat. As I found out with 2 out of the box brand new props they don’t always match what’s scratched on them.
- Location
- Missouri
Imma look into that.
- Location
- Missouri
UPDATE: Just too the ski out to the water after I ran a 1.5 needle restrictor into the water box. Literally a world of a difference. Much more responsive and has power like it never did before. Waterbox was definitely taking in too much water. I would say like 90% of the problems are gone. But I had done some research and lots of people say the RRP box is ass and it can make water go back into the engine. Which I did notice that happen like a couple times. I'm considering getting rid of it and going to a PFP box. It's much more baffled and it's not straight thru like the RRP.. but overall the ski runs insanely well right now.. might try to restrict the box a bit more. I ran some temps right after running the ski. The Box was about 110°, chamber was 115° and my engine was also about 115°. Those seem like reasonable temps?
- Location
- Ontario, Canada
Hah! I totally misread the title of the thread and thought it said need help dating my xs900... I've been single too long, ayye :/ lol
- Location
- Missouri
To all the guys running a RRP pipe with a PF water box, how do you inject water into the box? Just installed the box and ran it. At first it rips hard then it gets really hot and becomes sluggish. I checked the temps it got up to 220 degrees which is way too hot. How do you cool it down? Just run a bigger jet into the chamber? Or weld on a bung for the water box and inject water in it
DylanS
Gorilla Smasher
- Location
- Lebanon Pa
No waterbox injection here, 115 Jet at manifold at low 80’s water temp with no issues. If that’s not doing it for you you can add a bung for water injection if you’d like at the box too and adjust flow to that.
- Location
- Missouri
How hot does your water box get?
You are saying that the waterbox getting hot is causing the motor to be sluggish?
It would make a lot more sense if the CHAMBER getting hot was causing that, the temp of the waterbox shouldn't have much affect, only needs to be cooled to prevent damage to the couplers and hoses.
How hot does your chamber get?
It would make a lot more sense if the CHAMBER getting hot was causing that, the temp of the waterbox shouldn't have much affect, only needs to be cooled to prevent damage to the couplers and hoses.
How hot does your chamber get?
- Location
- Missouri
Chamber got to 140ish. Imma add a bigger jet into my manifold.